Clinicopathological characteristics of duodenal epithelial neoplasms: Focus on tumors with a gastric mucin phenotype (pyloric gland-type tumors)

Abstract

ObjectiveEpithelial tumors less commonly occur in the duodenum than in the stomach or large intestine. The clinicopathological characteristics of duodenal epithelial tumors remain a matter of debate. We therefore studied resected specimens to investigate the clinicopathological characteristics of duodenal epithelial tumors.Materials and methodsAmong duodenal epithelial tumors resected endoscopically or surgically in our hospital, we studied the clinicopathological characteristics of 110 adenomas or intramucosal carcinomas. The grade of atypia of all tumors was classified into 3 groups according to the World Health Organization (WHO) 2010 classification. The tumors were immunohistochemically evaluated to determine the frequency of differentiation toward fundic glands.ResultsAs for patient characteristics, there were 76 men (75.2%) and 25 women (24.8%), with a median age of 65 years (range, 34 to 84). The tumors most commonly arose in the first to second part of the duodenum. Many lesions were flat, and the median tumor diameter was 8.0 mm. The lesions were classified into 2 types according to mucin phenotype: intestinal-type tumors (98 lesions, 89.1%) and gastric-type tumors (12 lesions, 10.9%). Intestinal-type tumors were subdivided into 2 groups: tubular-type tumors (91 lesions, 82.7%) and tubulovillous-type tumors (7 lesions, 6.4%). Gastric-type tumors were classified into 2 types: foveolar type (3 lesions, 2.7%) and pyloric gland-type (PG) tumors (9 lesions, 8.2%). The grade of atypia was significantly higher in gastric-type tumors (p<0.01). PG tumors were gastric-type tumors characterized by pyloric glands and findings suggesting differentiation toward fundic glands.ConclusionsAbout 10% of the duodenal tumors had a gastric-type mucin phenotype. Gastric-type tumors showed high-grade atypia. In particular, PG tumors showed similarities to PG tumors of the stomach, such as differentiation toward fundic glands.

Clinicopathological characteristics of non‐ampullary duodenal tumors and their phenotypic classification

“…However, this finding was not statistically significant. Categorization according to phenotype was found to be necessary because a higher rate of malignancy was observed in G‐type NADETs, suggesting a more aggressive behavior than I‐type NADETs . As reported by Ushiku et al and Xue et al , G‐type cases demonstrated a poor prognosis since most cases involved advanced cancers .…”

“…Another strong point of our study was that the population included submucosal cancers. Mitsuishi et al and Toba et al reported clinicopathological features of NADETs, and mentioned the malignant potential of G‐type NADETs . However, there were few cases of submucosal cancer.…”

“…Although the strong relationship between the tumor location, histologic grade, and its phenotype is highly anticipated, it is not well‐described. Furthermore, even though the malignant potential of G‐type NADETs has been reported, it remains controversial …”

“…Furthermore, even though the malignant potential of G-type NADETs has been reported, it remains controversial. 3,[13][14][15][16] Therefore, we conducted an immunohistological review to elucidate the clinicopathological features of NADETs according to the tumor location and phenotypic classification. Additionally, we searched for independent predictive factors associated with G-type NADETs.…”

Clinicopathological Features and Magnifying Chromoendoscopic Findings of Non-Ampullary Duodenal Epithelial Tumors

“…These reports showed that NADETs of the gastric type have higher malignant potential than those of the intestinal type [14-15]. It has also been shown that the intestinal type is associated with a more favorable disease course, with a longer survival when compared with the other types [16].…”